4 YEAR PhD IN NEUROSCIENCE
Department of Neuroscience, Physiology & Pharmacology
Neuronal nicotinic acetylcholine receptors
Our research group uses a wide range of molecular biological and cell biological techniques to investigate the pharmacological and functional properties of neuronal nicotinic acetylcholine receptors (nAChRs). One of our main experimental approaches is to examine the properties recombinant nAChRs expressed in cultured cell lines. Our current research interests encompass both mammalian nAChRs (which are important targets for therapeutic drug discovery) and insect nAChRs (which are targets for the neonicotinoid insecticides). In addition to studies of the pharmacological and cell biological properties of nAChRs, a current focus of research in our lab is the role of nAChR-associated proteins such as RIC-3.
Millar lab homepage: http://www.ucl.ac.uk/npp/nm.html
Rotation projects will provide an opportunity to gain familiarity with a variety of molecular biological, cell biological and pharmacological techniques. They will be self-contained projects but will, typically, form part of an existing research project within the lab and will be designed with the expectation that they will provide data for planned research publications. It is anticipated that experience gained during rotation projects will form the foundation for independent PhD research projects, but it is likely that the precise focus of PhD projects will be influenced by a student’s particular research interests.
Brief summaries are provided below of three possible rotation projects. More detailed information can be obtained by contacting Neil Millar.
1) Molecular characterization of RIC-3, a nAChR-associated protein
RIC-3 is a recently identified nAChR-associated transmembrane protein which has a profound influence upon the folding, assembly and trafficking of nAChRs. RIC-3, was originally identified in C. elegans, but has also been cloned from several other species. This project will extent recent work in our laboratory on human RIC-3 homologues (Lansdell et al. 2005). A range of molecular and cell biological techniques will be employed to map domains critical to interactions with nAChR subunits and will examine the influence of RIC-3 upon targeting, trafficking and function of nAChRs.
2) Molecular pharmacological characterization of neuronal nAChRs
This project will examine the influence of subunit composition, subunit domains and of individual amino acids upon the pharmacological properties of neuronal nAChRs. The project will employ molecular biological techniques for the construction of nAChR subunit chimeras and will use site-directed mutagenesis to alter individual amino acids. Recombinant nAChRs will be studied using pharmacological techniques such as radioligand binding and fluorometric intracellular calcium assays.
3) Cell biological characterization of neuronal nAChRs
This project will examine the influence of subunit composition, subunit domains and of individual amino acids upon the intracellular targeting and trafficking of neuronal nAChRs. The project will employ molecular biological techniques for the construction of nAChR subunit chimeras and will use site-directed mutagenesis to alter individual amino acids. Recombinant nAChRs will be studied using cell biological and biochemical techniques such as immunofluorescent confocal microscopy and co-immunoprecipitation.
Broadbent, S., Groot-Kormelink, P.J., Krashia, P.A., Harkness, P.C., Millar, N.S., Beato, M. and Sivilotti, L.G. (2006)
Incorporation of the β3 subunit has a dominant negative effect on the function of recombinant central-type neuronal nicotinic receptors.
Molecular Pharmacology 70, 1350-1357
Ballestero, J.A., Plazas, P.V., Kracun, S., Gómez-Casati, M.E., Taranda, J., Rothlin, C.V., Katz, E., Millar, N.S. and Elgoyhen, A.B. (2005)
Effects of quinine, quinidine and chloroquine on α9α10 nicotinic cholinergic receptors.
Molecular Pharmacology 68, 822-829
Liu, Z., Williamson, M.S., Lansdell, S.J., Denholm, I., Han, Z. and Millar, N.S (2005)
A nicotinic acetylcholine receptor mutation conferring target-site resistance to imidacloprid in Nilaparvata lugens (brown planthopper).
Proceedings of the National Academy of Sciences USA 102, 8420-8425
Lansdell, S.J., Gee, V.J., Harkness, P.C., Doward, A.I., Baker, E.R., Gibb, A.J. and Millar, N.S. (2005)
RIC-3 enhances functional expression of multiple nicotinic acetylcholine receptor subtypes in mammalian cells.
Molecular Pharmacology 68, 1431-1438
Baker, E.R., Zwart, R., Sher, E. and Millar, N.S. (2004)
Pharmacological properties of α9α10 nicotinic acetylcholine receptors revealed by heterologous expression of subunit chimeras.
Molecular Pharmacology 65, 453-460.
Craig, P.J., Bose, S., Zwart, R., Beattie, R.E., Folly, E.A., Johnson, L.R., Bell, E., Evans, N.M., Benedetti, G., Pearson, K.H., McPhie, G.I., Volsen, S.G., Millar, N.S., Sher, E. and Broad, L.M. (2004)
Stable expression and characterisation of a human α7 nicotinic subunit chimera: a tool for functional high-throughput screening.
European Journal of Pharmacology 592, 31-40
Lansdell, S.J. and Millar, N.S. (2004)
Molecular characterization of Dα6 and Dα7 nicotinic acetylcholine receptor subunits from Drosophila: formation of a high-affinity α-bungarotoxin binding site revealed by expression of subunit chimeras.
Journal of Neurochemistry 90, 479-489